Draba surculosa Franch.

Draba surculosa is highly variable in the density of indumentum and the relative amounts of simple and stellate trichomes. Some forms are subglabrous except on the leaf margins, while others have an abundance of simple trichomes on both leaf surfaces. Among such forms is the type collection of D. balangshanica, Expedition Wolong Panda Research 877 (isotype, PE), which is remarkably similar to that of D. surculosa except for the abundance of simple instead of stellate trichomes on the abaxial leaf surface.

Herbs perennial, (7-)10-45(-82) cm tall, not canescent. Caudex branches many, surculose, terminated in rosettes. Stems erect or decumbent, simple, sparsely or rarely densely pubescent with a mixture of simple and sessile stellate trichomes, apically tomentose with appressed stellate ones. Basal leaves rosulate, persistent, sessile, oblanceolate to obovate or oblong, 1-4 cm × 3-7 mm, abaxially sparsely pubescent with stalked, 3- or 4-rayed stellate trichomes, sometimes glabrescent except for margin and midvein, adaxially with a mixture of primarily simple trichomes and fewer stellate ones, rarely exclusively simple, base cuneate, margin dentate or entire, apex obtuse. Cauline leaves (3-)7-17(-30), sessile; leaf blade oblong, lanceolate, or ovate, 1.5-5(-8) × 0.5-1.5 cm, pubescent as basal leaves, base obtuse, often auriculate or amplexicaul, margin dentate or entire, apex obtuse or acute. Racemes (12-)20-60(-120)-flowered, bracteate basally or to near apex, elongated considerably in fruit. Fruiting pedicels (0.5-)1-2.2(-2.7) cm, divaricate, straight or curved upward, glabrous adaxially, pubescent abaxially with appressed stellate trichomes. Sepals oblong or ovate, 2-3(-3.5) × 1-1.5(-2) mm, ascending, abaxially sparsely pilose with primarily simple trichomes, base of lateral pair subsaccate, margin membranous. Petals yellow, obovate, 5-8 × (2-)2.5-4 mm, apex emarginate; claw 1-2 mm. Filaments 2-3.5 mm; anthers oblong, 0.6-0.9 mm. Ovules 8-12 per ovary. Fruit oblong, elliptic, or elliptic-linear, (0.7-)1-1.5(-2) cm × 3-5 mm, latiseptate, sometimes slightly twisted; valves glabrous, with a distinct midvein extending full length; style 0.5-1.5 mm. Seeds brown, ovate, 1.6-2.5 × 1-1.5 mm. Fl. Jun-Aug, fr. Jul-Sep.

Sichuan, Xizang, Yunnan.

* Grassy slopes, pastures, rock crevices, alpine meadows, thickets, ravines, scree; 2600-4600 m.

Draba amplexicaulis Franchet var. bracteata O. E. Schulz; D. balangshanica W. T. Wang; D. mairei H. Léveillé; D. moupinensis Franchet.